The y-intercept exists when x = 0, so the y-intercept is (0, 30). The zeroes are found by factoring. You can simplify that a bit by factoring out a 6: [tex]f(x)=6( x^{2} +3x+5)[/tex]. Now factor that using the quadratic formula because the solutions are not real. [tex]x= \frac{-3+/- \sqrt{(3) ^{2}-4(1)(5) } }{2} [/tex] which simplifies to [tex]x= \frac{-3+/- \sqrt{-11} }{2} [/tex] and in the end we have [tex]x= \frac{-3+/-i \sqrt{11} }{2} [/tex]